Acid catalyzed modification of cellulosic materials with methylolated, halo-cyanoacetamides



United States Patent Q A non-exclusive, irrevocable, royalty-free license in the invention herein described, throughout the world for all purposes of the United States Government, with the power to grant sublicenses for such purposes, is hereby granted to the Government of the United States of America.

This invention relates to halogen containing methylolamides and polymeric derivatives thereof; to methods for' preparing the said halogen containing methylolamides and the said polymeric derivatives thereof; and to a process for utilizing these compounds. More specifically, this invention relates to halo-cyanoacetamides, to new methylol derivatives prepared from halo-cyanoacetamides, and methods for preparing and using these as finishes for cellulosic textiles.

One object of this invention is the preparation of methyloldihalocyanoacetamides from dihalocyanoacetamides.

A second object of this invention is the preparation of finishing agents for cellulosic textiles.

The compounds of this invention are particularly useful as finishing agents for cellulosic textiles in that when these compounds are applied to cellulosic textiles the said textiles are rendered wrinkle-resistant, rot-resistant, flameresistant, and the finish is resistantto both acid and base hydrolysis.

The equations applicable to the preparation of compounds of our invention-wherein X is a halogen, including fluorine, chlorine, bromine, and iodine.are presented here to facilitate the teaching of the art of our invention.

E quations:

O l 1 l I NEG-CHzl-NHz 2X1 NEG-([l-(E-NH: 2HX

X. cyanoaeetarnide X dimethyloldinalocyanoacetamlde CHi O-CelIuIOSe gen and formaldehyde content of cotton fabric treated with dimethylol acetamide are greatly reduced by hydrolysis. The methylol derivatives of this invention, i.e., the methylol derivatives of dihalocyanoacetamides, offer a definite advantage over the prior art in that the finish on the cotton is much more resistant to removal by hydrolysis, and hence is more stable to hydrolytic conditions encountered in laundering. This hydrolytic stability is due to the presence of the strongly electron-withdrawing groups-Cl, Br, and CEN. A further advantage over the prior art is a significant degree of flame resistance imparted to the cotton due to the presence of the halogens.

The methylol derivatives of dichlorocyanoacetamide and dibromocyanoacetamide of this invention can be prepared by bringing into reactive combination the amide and formaldehyde in aqueous alkaline solution. The reaction takes place at room temperatures about from 25 to 45 C.

In general, the methylolation reaction is carried out in mole ratios of amide to formaldehyde of about from 1:1 to 1:3. The reaction is carried out in aqueous solutions adjusted to pH about from 7.0 to 9.0 With an alkali metal hydroxide, such as sodium hydroxide. The reaction usually reaches equilibrium in about from 18 to 24 hours, and probably contains a mixture of the monomethylol and dimethylol derivatives. The methylolamides are not isolated from the solutions before application to cellulosic textiles. To minimize polymerization, the solutions are preferably stored in a refrigerator until ready to be used.

During the reaction of formaldehyde with dichlorocyanoacetamide and di-bromocyanoacetamide, small amounts of White solid polymer precipitated. The polymers contain nitrogen and the corresponding halogen. V

Cellulosic textile fiber, yarns, and fabrics can be made wrinkle resistant in accordance with this invention. The process consists essentially of impregnating the textile materials with an aqueous solution of the methylol derivatives, and curing the impregnated materials at temperatures conventionally used for curing cellulosic textiles.

The time and temperature required for curing the impregnated textile is dependent on the particular compound and upon-the weight of fabric being treated. The temperature can range aboutfrom 100 to 160 C. For the bromine containing compound, at temperatures above about 140 C., the fabric becomes degraded due to the low decomposition point of the resin on the cellulosic material. This-resin would be useful in those cases where resins with low decomposition points are desirable. The curing time of the material on the fabric can vary about from 1 to 30 minutes. The rapid cures are accomplished at the higher temperatures. v

Simultaneous polymerization within and crosslinking of the cellulose molecules of the fibers providedby this inventionare produced in the presence of an .acid catalyst. Catalysts suitable for the reaction are those conventionally used in applying methylol amides to cellulosic materials. These catalysts are Lewis acids and protonic acids, and include latent acid catalysts, such as magnesium chloride, zine nitrate, zinc fluo'borate, and amine hydrochlorides.

When a cotton textile is being treated, it is advantageous to pass it through the impregnating liquor to thoroughly wet it and remove excess liquor by passing the lied to cotton. However, the wrinkle resistance and nitrowetted textile through squeeze rolls. It is also advanta geous to dry the textile at a temperature of about from 60 to 100 C. before curing. Preferred drying is carried out at about from to C. for about three to five minutes, while preferred curing is carried out at about from to C. for about from three to five min- '5 =3 utes, the longer periods of time being employed with the lower temperatures.

The degree of flame resistance, crease resistance, and rot resistance can be varied by varying the amount of acetamide. The solution was diluted with water to 14% and used to treat samples of cotton printcloth. The solution was divided into four parts. A different catalyst was added to each part (indicated in Table I) before treatpolymer and crosslinking put into the textile. 5 ment of the fabric. The fabric samples were padded Limits and referred ran 8, through the solutions by conventional padding procedures p g to a wet pickup of approximately 75%. The samples were For preparation of the methylol derivatives, the limits dried in an oven at 85 C. for five minutes and then cured of reaction temperature are about from 0 to 45 C. The in an oven for five minutes at the temperatures indicated preferred range is about from to C. The limits of 10 in Table I. The samples were washed in hot water and reaction time are about from one hour to 24 hours. The dried.

TABLE I Wrinkle Recovery Sample Type Catalyst Catalyst, Solution pH Curing Add-On, Angles Number Percent Temp., 0. Percent (W%r r1 l and 1 Degrees Z11(NO3)26H2O 1.0 6 45 145 3.7 235 ZI1(NO3)2-6H2O 1. 0 6.45 150 4. 4 241 ZI1(BF4)2 1. 6 4. 0 140 5.1 252 zn(BFi 1. 6 4. 0 150 6.3 260 Amine hydrochloride- 0.7 6. 5 140 6. 3 233 do 0. 7 6. 5 150 7. 7 268 MgClz-GH: 3.0 6.4 140 5.6 267 MgClg-GHaO 3.0 6.4 150 5. 3 282 Control had wrinkle recovery angle (warp and fill) of 188.

preferred range is about from 18 to 24 hours. The limits of mole ratio of halocyanoacetamide to formaldehyde are about from 1:1 to 1:3. The preferred ratio is 1:2.

For the application of the methylol derivatives to cotton, the limits of drying time and temperature are about from one to ten minutes at about from 50 to 100 C. The preferred range is about from three to five minutes at about from 85 to 100 C. The limits of curing time and temperature are about from one to ten minutes at about from 100 to 160 C. The preferred range is about from three to five minutes at about from 135 to 145 C.

The following examples illustrate the methods of carrying out the invention; however, the examples are not meant to limit the invention in any manner whatever. The fabrics treated by process of this invention as well as the controls were tested by the standard methods recommended by the American Society for Testing Materials, Philadelphia, Pa., Committee D-13. Breaking strength was determined by the one-inch strip method, ASTM designation D39-59; tearing strength by the Elmendorf method, ASTM designation D1295-60T; wrinkle recovery by the Monsanto method, ASTM designation D1424-59; rot resistance by the soil-burial method, ASTM designation D684-54; and flame resistance by the standard vertical method, Federal Specification CCCT191b. All percentages and parts are by weight.

EXAMPLE 1 96.8 parts of dibromocyanoacetamide, 100 parts of 36.3% aqueous formaldehyde, and 201.4 parts of water were mixed in a flask. This was a mole ratio of dibromocyanoacetamide to formaldehyde of 1:2. To the stirred mixture was added dropwise 4.3 parts of 12.5% aqueous sodium hydroxide. During the addition of the sodium hydroxide, the temperature rose spontaneously to 50 C. The temperature was not allowed to go above 50 C. by external cooling. The pH of the solution at the end of the sodium hydroxide addition was 9.6. The solution was stored in a refrigerator overnight. A small amount of white precipitate formed (2.6 parts) which was filtered and washed with acetone. The white solid was a polymer containing 9.52% nitrogen and 52.98% bromine.

The clear filtrate had changed to a pH of 6.8 on standing overnight. The solution contained theoretically about 29% of the formaldehyde derivative of dibromocyano- All of the samples cured at 150 C. were discolored, indicating that 140-145 C. is a more desirable temperature. Also, samples treated at 150 had greater strength losses than those treated at 140-145 C. All of the samples exhibited some flame resistance.

EXAMPLE 2 A solution containing 20% of the formaldehyde derivative of dibromocyanoacetamide was prepared as in Example 1. To the solution was added 1.2 parts of per parts of solution. The solution was padded on to a sample of cotton printcloth as in Example 1. The fabric was dried for five minutes at 85 C. and cured at C. for five minutes. The fabric had a resin add-on of 8.5%. Data on wrinkle recovery, strength, and elemental analysis before and after laundering and hydrolysis are shown in Table II.

'(a) After ten washes.

(b) After acid hydrolysis at pH 4.

(e) After base hydrolysis at pH 10.

((1) After stripping with urea-phosphoric acid.

Acid hydrolysis was carried out by immersing the samples for thirty minutes at 80 C. in an aqueous solution buffered to pH 4. The base hydrolysis was carried out the same way except the solution was buffered to pH 10. The acid stripping was carried out by immersing the samples in a water solution containing 1.5% phosphoric acid and 5% urea, and heating for thirty minutes at 80 C. The data shows that the finish is resistant to laundering and acid and base hydrolysis as measured by wrinkle recovery, and elemental analysis.

EXAMPLE 3 A solution was prepared as in Example 1 except the mole ratio of dibromocyanoacetamide to formaldehyde was 1:3. The solution contained 48.4 parts of dibromo- A solution was prepared as in Example 1 except the mole ratio of dibromocyanoacetamide to formaldehyde was 1:1. The solution was diluted with water to a concentration of 27% based on the theoretical yield of a monomethylol derivative. To the solution was added 1.2 parts of Zn(NO -6H O per 100 parts of solution.

The solution was applied to cotton printcloth as in Example 1, dried five minutes at 100 C., and cured five minutes at 140 C. The fabric had a resin add-on of 8.7%, and a wrinkle-recovery angle of 235. It also had significant flame-resistance. The wrinkle recovery indicated crosslinking and hence the presence of some of the dimethylol derivative in the solution.

EXAMPLE 5 A solution was prepared as in Example 1 with the following quantities: 193.6 parts of dibromocyanoacetamide, 198.3 parts of 36.3% aqueous formaldehyde, 212.1 parts of water, and 5.5 parts of 12.5% aqueous sodium hydroxide. This was a mole ratio of dibromocyanacetamide to formaldehyde of 1:3. 1.2 parts of Zn(NO -6H O per 100 parts of solution was used as a catalyst. The solution was padded on to samples of cotton printcloth as in Example 1. The samples were dried for five minutes at 100 C. and cured for eight minutes at 140 C. The fabric had a resin add-on of 12.8%, and .a wrinkle-recovery angle of 285 (warp and filling). The breaking strength of the treated fabric was 26.6 lbs. The fabric was subjected to soil burial tests to determine rot resistance. After 18 weeks in soil burial beds, the samples had a breaking strength of 18.3 lbs. Since this was a strength retention of 69%, the fabric exhibited considerable rot resistance.

EXRMPLE 6 30.6 parts of dichlorocyanoacetamide, 33.0 parts of 36.3% aqueous formaldehyde, and 131.4 parts of water were mixed in a flask. This was a mole ratio of amide to formaldehyde of 1:2. While stirring, five parts of 12.5% aqueous sodium hydroxide were added dropwise over a period of about ten minutes. The temperature of the reaction rose spontaneously to 49 C. in about three minutes, but was cooled to 35 C. by external cooling and maintained at this temperature during the remainder of the addition time. The pH was 9.9. After standing for one hour at room temperature, the pH had changed to 6.85. It was made to a pH 8.5 by the addition of more sodium hydroxide..After 1.5 hours more, the pH had changed to 6.75. It was made to pH 8.5 again and allowed to stand overnight at 10 C. Assuming a theoretical yield of the dimethylol derivative, the solution was diluted with water to a solution. The solution was divided into three parts and MgCl -6H O added as a catalyst in concentrations indicated in Table ,III. The solutions were padded on to samples of cotton printcloth as in Example 1. They were dried for five minutes at 85 C., and cured for five minutes 160 C., washed in hot water, and dried. Resin add-on, strength, and wrinkle-recovery angles are shown in Table III.

TAB LE III Break- Tearing Wrinkle- MgCl -fiHzO Resin ing strength recovery Sample conc., Addon strength (filling), angles, Number percent percent (filgng) gms. degrees The untreated fabric had a wrinkle recovery angle of 188. The data shows that there was an improvement in wrinkle recovery, although it was not as great as that obtained with dibromocyanacetamide. There was a small degree of flame resistance. The dibromocyanoacetamide was more effective as a flame retardant.

EXAMPLE 7 A solution was prepared as in Example 6. The solution was divided into two parts and labeled Solution I and Solution II. Solution I was diluted with water to a concentration of about 10% based on the dimethylol derivative. Zn(NO -6H O was added as a catalyst to provide a concentration of four parts per 100 parts of solution. Solution II was diluted with water to a concentration of about 15 based on the dimethylol derivative.

was added as a catalyst to provide a concentration of four parts per 100 parts of solution. Samples of cotton printcloth were padded with the solution as in Example 1. The samples were dried for five minutes at C. and cured for five minutes at 160 C., washed, and dried. The fabric treated with Solution I had a wrinkle-recovery angle of 268 (warp and filling), and the fabric treated with Solution II, 229 (warp and filling).

EXAMPLE 8 The reaction of formaldehyde with dichlorocyanoacetamide was carried out as in Example 6. When the reaction was completed a small amount of white polymer had precipitated. The polymer contained 12.2% nitrogen, 30.8% chlorine, and 12.1/ formaldehyde.

We claim:

1. A process for treating cellulosic textile material comprising:

(a) wetting the cellulosic textile material with an aqueous solution of the composition prepared by reacting in a basic aqueous solution dibromocyanoacetamide with formaldehyde in a mole ratio of about from 1:1 to 1:3 and about from 1.0% to 3.0% by weight of an acid-type catalyst, and

(b) curing the fabric at about from to C., for about from one to ten minutes, the higher temperatures used with the shorted periods of time.

2. A process for treating cellulosic textile material comprising:

(a) wetting the eellulosic textile material with an aqueous solution of the composition prepared by reacting in a basic aqueous solution dichlorocyanoacetamide with formaldehyde in the mole ratio of about from 1:1 to 1:3 and about from 1.0% to 3.0% by weight of an acid-type catalyst, and

(b) curing the fabric at about from 100 to C.,

for about from one to ten minutes, the higher temperatures used with the shorter periods of time.

No references cited.

70 NORMAN G. TORCHIN, Primary Examiner.

I. CANNON, Assistant Examiner. 

1. A PROCESS FOR TREATING CELLULOSIC TEXTILE MATERIAL COMPRISING; (A) WETTING THE CELLULOSIC TEXTILE MATERIAL WITH AN AQUEOUS SOLUTION OF THE COMPOSITION PREPARED BY REACTING IN A BASIC AQUEOUS SOLUTION DIBROMOCYANOACETAMIDE WITH FORMALDEHYDE IN A MOLE RATIO OF ABOUT FROM 1:1 TO 1:3 AND ABOUT FROM 1.0% TO 3.0% BY WEIGHT OF A ACID-TYPE CATALYST, AND (B) CURING THE FABRIC ABOUT FROM 100* TO 140*C., FOR ABOUT FROM ONE TO TEN MINUTES, THE HIGHER TEMPERATURE USED WITH THE SHORTED PERIODS OF TIME. 